According to the development of cells having a high voltage and a high capacity, a large number of various polymeric electrolytes and nonaqueous electrolytes have been proposed. However, polymeric electrolytes and nonaqueous electrolytes have an ionic conductivity which is lower than that of aqueous electrolytes by more than one figure. Further, for example, a polymeric electrolyte using polyethylene glycol has defects that it is low in transfer and transport rates of charge carrier ions. Thus, attempts of improvement have been made by using various methods.
Meanwhile, when nonaqueous electrolytes are applied to cells, they are problematic in that charge/discharge efficiency and cycle characteristics are low. Therefore, in order to improve these, a solvent composition of an electrolytic solution and a type of a support salt has been studied, and a system in which an additive is added to a nonaqueous electrolyte has been studied. For example, Japanese Patent Laid-Open No. 3,728/1999 discloses a nonaqueous electrolytic solution secondary cell comprising a positive electrode and a negative electrode containing a material capable of occluding and releasing lithium reversibly, a nonaqueous electrolytic solution containing a lithium salt and a separator, at least one organic boron compound being contained in the cell in a predetermined amount.
However, these prior techniques have posed a problem that an effective concentration region of an additive is narrow and further an effect provided by its addition per weight is small.
In view of the foregoing, the invention has been made, and aims to provide a polymeric electrolyte and a nonaqueous electrolyte which increases a dissociation degree of an electrolytic salt, which can improve a transport rate of charge carrier ions and in which an effective concentration region of an additive is wide and an effect provided by its addition per weight is great, and an electric device using the same.